What was found
SEA FLIGHT NR 2490: MASTER WARNING: MAIN AFT BAGGAGE DOOR INDICATES OPEN. AIRCRAFT RETURNED TO BLOCK. MAINTENANCE FOUND AFT BAGGAGE DOOR HANDLE SEATED, SECURED AND LOCKED ON RETURN TO GATE. FOUND 'ABDRLK' OPEN FAULT IN THE PROX SENSOR COMPUTER. OPENED AND CLOSED DOOR NUMEROUS TIMES. DOOR ALWAYS INDICATES CLOSED AND LOCKED. PRESSURIZED AIRCRAFT. ALL DOORS ALWAYS INDICATE CLOSED AND LOCKED. UNABLE TO INDUCE FAULT. ALWAYS CHECKED GOOD DURING TESTING. NO PARTS REPLACED. AIRCRAFT RETURNED TO SERVICE.